According to structures, touch panels can be classified into Add on Mode Touch Panels, On Cell Touch Panels and In Cell Touch Panels. For an in-cell touch panel, touch electrode of the touch panel is provided inside a liquid crystal display screen, so that the overall thickness of a module can be reduced, and the manufacture cost of the touch panel can also be greatly lowered. According to working principles, touch panels can be classified into resistive touch panels, capacitive touch panels, etc. A capacitive touch panel supports multi-point touch function, and has relatively high transmittance, relatively low overall power consumption, high hardness of contact surface and long service life.
At present, an existing capacitive in-cell touch panel is realized by directly adding touch scanning lines and touch sensing lines on an existing array substrate, that is, two layers of strip-shaped electrodes intersecting with each other in different planes are fabricated on a surface of the array substrate, the two layers of electrodes serve as touch driving lines and the touch sensing lines of the touch panel, respectively, and mutual capacitance is formed at a position where two electrodes intersect with each other in different planes. The working process of the touch panel is as follows: when touch driving signals are applied to the electrodes serving as the touch driving lines, voltage signals coupled to the touch sensing lines by the mutual capacitances are detected, during this process, when a human body contacts with the touch panel, the electric field of the human body will act on the mutual capacitance, so that the value of the mutual capacitance is changed, and the voltage signals coupled to the touch sensing lines are thus changed. As a result, the position of a contact point can be determined according to the change of the voltage signals.
In the above structure design of the capacitive in-cell touch panel, as touch scanning lines and touch sensing lines need to be provided additionally on an existing array substrate, the number of masking times in a manufacturing process will be increased, the thickness of the touch panel is also increased and the manufacture cost is thus increased. Moreover, the touch driving signals applied to the added touch scanning lines may interfere with the original display signals in the array substrate, so that the quality of displayed pictures and the accuracy of touch control are influenced.
Therefore, how to reduce the number of masking times in a manufacturing process, reduce the thickness of a touch panel and avoid the mutual interference between touch driving signals and display signals is the technical problem to be solved by those skilled in the art.